There's much more to a roof than just the slates or tiles. Every change of pitch, junction or interconnection requires a special construction. For example lead flashings and soakers around the chimney, GRP trays in valleys or treatment of roof ridge.
Images 1 shows selective repairs to tile roof and new fascia timbers being fitted.
Image 2 shows new tile roof with mechanically fixed dry ridge tiles, uPVC dry verge and uPVC cladding.
The Building Regulations require that a mechanically fixed dry ridge system must be installed on new pitched roofs.
The traditional method of ridge tiles bedded in mortar is no longer permitted. The mechanically fixed system offers two advantages: it is more secure and it provides the option to incorporate roof ventilation.
Even if you are not having a full roof replacement it is a wise precaution to take the opportunity to have a mechanically fixed dry ridge system installed.
With global warming more extreme weather is to be expected. The ridge tiles at the top of the roof contribute significantly to the stability of the entire roof.
Cooking, cleaning, washing — these are all activities that generate moisture.
In older homes with draughty windows and open fires all this moisture is vented to the open air.
In modern homes the water vapour can become trapped.
It can soak into the fabric of the building and cause rot, mould growth and structural damage.
Warm moist air rises and for this reason adequate roof ventilation is important. Exactly how to provide this vapour release ventilation will depend on the way the roof has been constructed and how any thermal insulation has been positioned. Ventilation may be provided by cross flow eaves ventilators, tile ventilators or via a mechanically fixed ridge venting system.
Making repairs to a roof means bringing together a wide range of materials and the skills necessary to use them.
Consider the range of components necessary to construct a roof: timbers, sarking membrane, slates or tiles, lead for flashings, GRP (Glass Reinforced Polyester) for valleys, uPVC for verge caps and rainwater goods. All these materials have specific installation requirements.